302 PEEFACE. Schott), and more recently by Dr. Rothrock, upon this Survey, and by Mrs. Sumner, the wife of the commander of the United States forces at Camp Bowie. Dr. Edward Palmer and a few other persons have also sent Ferns from this region. In Western Texas and the eastern part of New Mexico, Mr. Charles Wright, Mr. August Fendler, and Mr. F. Lindheimer made large collections of plants, Ferns among them, between 1843 and 1852. The Ferns of the mountains of Colorado have been collected by Dr. Parry and Messrs. Hall and Harbour in 1861-1864, by Dr. George Vasey in 1868, and by other botanists of the Interior Department Surveys, by Prof John Wolf, expedition of 1873 of this Survey, and especially by Mr. Townshend S. Brandegee, who has resided several years at Canon City, Colorado. Other parties have from time to time made small collections in the same region. The Ferns of Northern Nevada and Utah, just on the border of the region embraced in the following report, were collected by Mr. Sereno Watson, of Clarence King's Survey of the 40th parallel, and to a small extent in Utah by myself From Southern Utah, Drs. Palmer and Parry have sent good collections. From Southern Nevada very little in the way of Ferns has been received. In order to extend the usefulness of this report, a few Ferns which occur either in Texas or in the extreme Northwest, outside of our assigned limits, and which are more or less likely to be found within them, are inserted in their proper places. Several additional species have been received while I have been pre¬ paring this report, and it is very probable that still other species wiU be discovered in the future. The genera Scolopendrimn, Camptosorus, Struthiopteris, Onoclea, Dick-sonia, Schizcea, Lygodium, and, most remarkable of all, Osmunda, have never,to my knowledge, been discovered in any part of the territory west of theRocky Mountains. DANIEL C EATON. New Haven, Conn., Sept. 22, 1877.